From 44626e60bf2bac53e2e3988874d310e7882eaabf Mon Sep 17 00:00:00 2001
From: Runxi Yu <me@runxiyu.org>
Date: Fri, 21 Mar 2025 16:55:53 +0800
Subject: [PATCH] Output git logs incrementally

---
 git_misc.go               | 35 +++++++++++++++++++++++++++++++++++
 http_handle_repo_index.go |  9 ++++++---
 http_template_funcs.go    |  4 ++++
 resources.go              |  9 +++++----
 templates/repo_index.tmpl |  3 +++
 templates/repo_log.tmpl   |  3 +++

diff --git a/git_misc.go b/git_misc.go
index cd2dc4dc4a8dcd42b0d49e792c069195eedf9e10..5b199650fd2d1b13e9000977bd3b0c9902fd4041 100644
--- a/git_misc.go
+++ b/git_misc.go
@@ -7,6 +7,7 @@ import (
 	"context"
 	"errors"
 	"io"
+	"iter"
 	"os"
 	"strings"
 
@@ -94,6 +95,40 @@
 		displayTree = append(displayTree, displayEntry)
 	}
 	return displayTree
+}
+
+func commitIterSeqErr(commitIter object.CommitIter) (iter.Seq[*object.Commit], *error) {
+	var err error
+	return func(yield func(*object.Commit) bool) {
+		for {
+			commit, err2 := commitIter.Next()
+			if err2 != nil {
+				if errors.Is(err2, io.EOF) {
+					return
+				}
+				err = err2
+				return
+			}
+			if !yield(commit) {
+				return
+			}
+		}
+	}, &err
+}
+
+func iterSeqLimit[T any](s iter.Seq[T], n uint) iter.Seq[T] {
+	return func(yield func(T) bool) {
+		var i uint
+		for v := range s {
+			if i > n-1 {
+				return
+			}
+			if !yield(v) {
+				return
+			}
+			i++
+		}
+	}
 }
 
 func getRecentCommits(repo *git.Repository, headHash plumbing.Hash, numCommits int) (recentCommits []*object.Commit, err error) {
diff --git a/http_handle_repo_index.go b/http_handle_repo_index.go
index cb3fcdcbcb7f42111c9686e4ab083fd8194f609f..a22c75f9016937029e2e8aadd317d888480b5387 100644
--- a/http_handle_repo_index.go
+++ b/http_handle_repo_index.go
@@ -4,6 +4,7 @@
 package main
 
 import (
+	"iter"
 	"net/http"
 	"strings"
 
@@ -19,7 +20,8 @@ 	var repoName string
 	var groupPath []string
 	var refHash plumbing.Hash
 	var err error
-	var recentCommits []*object.Commit
+	var commitIter object.CommitIter
+	var commitIterSeq iter.Seq[*object.Commit]
 	var commitObj *object.Commit
 	var tree *object.Tree
 	var notes []string
@@ -46,10 +48,11 @@ 		})
 	}
 	params["branches"] = branches
 
-	if recentCommits, err = getRecentCommits(repo, refHash, 3); err != nil {
+	if commitIter, err = repo.Log(&git.LogOptions{From: refHash}); err != nil {
 		goto no_ref
 	}
-	params["commits"] = recentCommits
+	commitIterSeq, params["commits_err"] = commitIterSeqErr(commitIter)
+	params["commits"] = iterSeqLimit(commitIterSeq, 3)
 
 	if commitObj, err = repo.CommitObject(refHash); err != nil {
 		goto no_ref
diff --git a/http_template_funcs.go b/http_template_funcs.go
index 9609e61971efb9bf65ba39fc943f4f745f9660f0..5395b92a4612f2b075d75c04ddbb4d0efd92c76f 100644
--- a/http_template_funcs.go
+++ b/http_template_funcs.go
@@ -25,3 +25,7 @@
 func queryEscape(s string) string {
 	return url.QueryEscape(s)
 }
+
+func dereference[T any](p *T) T {
+	return *p
+}
diff --git a/resources.go b/resources.go
index c1b4a9b3be156ba02a07aa0ed14f89693cee649d..2576c12d4bf194868d160e1151e250638edcc5c6 100644
--- a/resources.go
+++ b/resources.go
@@ -40,10 +40,11 @@ 	m := minify.New()
 	m.Add("text/html", &html.Minifier{TemplateDelims: [2]string{"{{", "}}"}, KeepDefaultAttrVals: true})
 
 	templates = template.New("templates").Funcs(template.FuncMap{
-		"first_line":   firstLine,
-		"base_name":    baseName,
-		"path_escape":  pathEscape,
-		"query_escape": queryEscape,
+		"first_line":        firstLine,
+		"base_name":         baseName,
+		"path_escape":       pathEscape,
+		"query_escape":      queryEscape,
+		"dereference_error": dereference[error],
 	})
 
 	err = fs.WalkDir(resourcesFS, "templates", func(path string, d fs.DirEntry, err error) error {
diff --git a/templates/repo_index.tmpl b/templates/repo_index.tmpl
index 19814ccc8a038d39be81dc1694bad82742e998a1..d59e480416db268e4aabb8760fb2f7458fbcc8ca 100644
--- a/templates/repo_index.tmpl
+++ b/templates/repo_index.tmpl
@@ -90,6 +90,9 @@ 									{{- .Author.When.Format "2006-01-02 15:04:05 -0700" -}}
 								</td>
 							</tr>
 						{{- end -}}
+						{{- if dereference_error .commits_err -}}
+							Error while obtaining commit log: {{ .commits_err }}
+						{{- end -}}
 					</tbody>
 				</table>
 			</div>
diff --git a/templates/repo_log.tmpl b/templates/repo_log.tmpl
index 64e6783989551be8a2dd9ba72b1245fc323726a7..ac5f5549e14b666ecc2c1dda49101a6e1c76f7c7 100644
--- a/templates/repo_log.tmpl
+++ b/templates/repo_log.tmpl
@@ -37,6 +37,9 @@ 								{{- .Author.When.Format "2006-01-02 15:04:05 -0700" -}}
 							</td>
 						</tr>
 					{{- end -}}
+					{{- if dereference_error .commits_err -}}
+						Error while obtaining commit log: {{ .commits_err }}
+					{{- end -}}
 				</tbody>
 			</table>
 		</div>

-- 
2.48.1